Generally, an electro-wetting display panel includes an upper electrode, a lower electrode, and a polar fluid as well as a non-polar fluid sandwiched between the two electrodes. A method for operating the electro-wetting display panel is that, when voltage is not applied, the non-polar fluid spreads over a pixel unit so that an incident light can be absorbed by the non-polar fluid, and the pixel unit presents a dark state consequently. In addition, when the pixel unit presents a bright state, the voltage is applied to the upper and lower electrodes so that the non-polar fluid is concentrated and the proportion of the non-polar fluid in the pixel unit is reduced. Consequently, a reflective layer or light source under the non-polar fluid is exposed, such that the incident light is reflected by the reflective layer or the light of the light source may pass through an exposed region of the pixel unit to present a bright state.
Generally speaking, the voltage may be applied through an active device (such as a thin film transistor) in the pixel unit, wherein the active device mostly uses an electrode formed of an opaque metal for transmitting signals. The active device has to maintain the transmission of electrical signals, causing the non-polar fluid unable to be stably concentrated in a region above the active device. Therefore, in the known designs, in a state where the voltage is applied to the pixel unit, the region occupied by the concentrated non-polar fluid and the region where the active device is located are independent of each other; meanwhile, both regions do not reflect light or unable to be passed through by light, that is, they are unable to become effective display regions, which restricts the display aperture ratio of the electro-wetting display panel.